| /* Copyright (C) 1998-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Thorsten Kukuk <kukuk@uni-paderborn.de>, 1998. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <assert.h> |
| #include <errno.h> |
| #include <pwd.h> |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <unistd.h> |
| #include <sys/mman.h> |
| #include <sys/socket.h> |
| #include <sys/uio.h> |
| #include <sys/un.h> |
| #include <not-cancel.h> |
| #include <_itoa.h> |
| |
| #include "nscd-client.h" |
| #include "nscd_proto.h" |
| |
| int __nss_not_use_nscd_passwd; |
| |
| static int nscd_getpw_r (const char *key, size_t keylen, request_type type, |
| struct passwd *resultbuf, char *buffer, |
| size_t buflen, struct passwd **result); |
| |
| int |
| __nscd_getpwnam_r (const char *name, struct passwd *resultbuf, char *buffer, |
| size_t buflen, struct passwd **result) |
| { |
| if (name == NULL) |
| return -1; |
| |
| return nscd_getpw_r (name, strlen (name) + 1, GETPWBYNAME, resultbuf, |
| buffer, buflen, result); |
| } |
| |
| int |
| __nscd_getpwuid_r (uid_t uid, struct passwd *resultbuf, char *buffer, |
| size_t buflen, struct passwd **result) |
| { |
| char buf[3 * sizeof (uid_t)]; |
| buf[sizeof (buf) - 1] = '\0'; |
| char *cp = _itoa_word (uid, buf + sizeof (buf) - 1, 10, 0); |
| |
| return nscd_getpw_r (cp, buf + sizeof (buf) - cp, GETPWBYUID, resultbuf, |
| buffer, buflen, result); |
| } |
| |
| |
| libc_locked_map_ptr (static, map_handle); |
| /* Note that we only free the structure if necessary. The memory |
| mapping is not removed since it is not visible to the malloc |
| handling. */ |
| libc_freeres_fn (pw_map_free) |
| { |
| if (map_handle.mapped != NO_MAPPING) |
| { |
| void *p = map_handle.mapped; |
| map_handle.mapped = NO_MAPPING; |
| free (p); |
| } |
| } |
| |
| |
| static int |
| nscd_getpw_r (const char *key, size_t keylen, request_type type, |
| struct passwd *resultbuf, char *buffer, size_t buflen, |
| struct passwd **result) |
| { |
| int gc_cycle; |
| int nretries = 0; |
| |
| /* If the mapping is available, try to search there instead of |
| communicating with the nscd. */ |
| struct mapped_database *mapped; |
| mapped = __nscd_get_map_ref (GETFDPW, "passwd", &map_handle, &gc_cycle); |
| |
| retry:; |
| const char *pw_name = NULL; |
| int retval = -1; |
| const char *recend = (const char *) ~UINTMAX_C (0); |
| pw_response_header pw_resp; |
| |
| if (mapped != NO_MAPPING) |
| { |
| struct datahead *found = __nscd_cache_search (type, key, keylen, mapped, |
| sizeof pw_resp); |
| if (found != NULL) |
| { |
| pw_name = (const char *) (&found->data[0].pwdata + 1); |
| pw_resp = found->data[0].pwdata; |
| recend = (const char *) found->data + found->recsize; |
| /* Now check if we can trust pw_resp fields. If GC is |
| in progress, it can contain anything. */ |
| if (mapped->head->gc_cycle != gc_cycle) |
| { |
| retval = -2; |
| goto out; |
| } |
| } |
| } |
| |
| int sock = -1; |
| if (pw_name == NULL) |
| { |
| sock = __nscd_open_socket (key, keylen, type, &pw_resp, |
| sizeof (pw_resp)); |
| if (sock == -1) |
| { |
| __nss_not_use_nscd_passwd = 1; |
| goto out; |
| } |
| } |
| |
| /* No value found so far. */ |
| *result = NULL; |
| |
| if (__glibc_unlikely (pw_resp.found == -1)) |
| { |
| /* The daemon does not cache this database. */ |
| __nss_not_use_nscd_passwd = 1; |
| goto out_close; |
| } |
| |
| if (pw_resp.found == 1) |
| { |
| /* Set the information we already have. */ |
| resultbuf->pw_uid = pw_resp.pw_uid; |
| resultbuf->pw_gid = pw_resp.pw_gid; |
| |
| char *p = buffer; |
| /* get pw_name */ |
| resultbuf->pw_name = p; |
| p += pw_resp.pw_name_len; |
| /* get pw_passwd */ |
| resultbuf->pw_passwd = p; |
| p += pw_resp.pw_passwd_len; |
| /* get pw_gecos */ |
| resultbuf->pw_gecos = p; |
| p += pw_resp.pw_gecos_len; |
| /* get pw_dir */ |
| resultbuf->pw_dir = p; |
| p += pw_resp.pw_dir_len; |
| /* get pw_pshell */ |
| resultbuf->pw_shell = p; |
| p += pw_resp.pw_shell_len; |
| |
| ssize_t total = p - buffer; |
| if (__glibc_unlikely (pw_name + total > recend)) |
| goto out_close; |
| if (__glibc_unlikely (buflen < total)) |
| { |
| __set_errno (ERANGE); |
| retval = ERANGE; |
| goto out_close; |
| } |
| |
| retval = 0; |
| if (pw_name == NULL) |
| { |
| ssize_t nbytes = __readall (sock, buffer, total); |
| |
| if (__glibc_unlikely (nbytes != total)) |
| { |
| /* The `errno' to some value != ERANGE. */ |
| __set_errno (ENOENT); |
| retval = ENOENT; |
| } |
| else |
| *result = resultbuf; |
| } |
| else |
| { |
| /* Copy the various strings. */ |
| memcpy (resultbuf->pw_name, pw_name, total); |
| |
| /* Try to detect corrupt databases. */ |
| if (resultbuf->pw_name[pw_resp.pw_name_len - 1] != '\0' |
| || resultbuf->pw_passwd[pw_resp.pw_passwd_len - 1] != '\0' |
| || resultbuf->pw_gecos[pw_resp.pw_gecos_len - 1] != '\0' |
| || resultbuf->pw_dir[pw_resp.pw_dir_len - 1] != '\0' |
| || resultbuf->pw_shell[pw_resp.pw_shell_len - 1] != '\0') |
| { |
| /* We cannot use the database. */ |
| retval = mapped->head->gc_cycle != gc_cycle ? -2 : -1; |
| goto out_close; |
| } |
| |
| *result = resultbuf; |
| } |
| } |
| else |
| { |
| /* Set errno to 0 to indicate no error, just no found record. */ |
| __set_errno (0); |
| /* Even though we have not found anything, the result is zero. */ |
| retval = 0; |
| } |
| |
| out_close: |
| if (sock != -1) |
| __close_nocancel_nostatus (sock); |
| out: |
| if (__nscd_drop_map_ref (mapped, &gc_cycle) != 0) |
| { |
| /* When we come here this means there has been a GC cycle while we |
| were looking for the data. This means the data might have been |
| inconsistent. Retry if possible. */ |
| if ((gc_cycle & 1) != 0 || ++nretries == 5 || retval == -1) |
| { |
| /* nscd is just running gc now. Disable using the mapping. */ |
| if (atomic_decrement_val (&mapped->counter) == 0) |
| __nscd_unmap (mapped); |
| mapped = NO_MAPPING; |
| } |
| |
| if (retval != -1) |
| goto retry; |
| } |
| |
| return retval; |
| } |